Communication devices used in networks such as gateway devices for connection to the internet or wireless communication systems are increasingly multi-mode and multi-standard devices. Consequently such devices require the use of several different antennas integrated into the one device. The inclusion of several antennas in a device of reduced dimensions increases the mechanical constraints and performance. Indeed, the antennas should be able to operate in the presence of many mechanical parts and electrical components that may interfere with their radiation performances. Moreover, the location of the antennas in the device is also a challenge. With respect to radiation performance, there is a need to resolve isolation problems between radio frequency systems operating in different frequency ranges. Hence, a low ECC (envelope correlation coefficient) is used in MIMO systems (Multiple Input Multiple Output), the antennas of the MIMO systems being strongly isolated to respond to the maximum capacity of the channel used. Moreover, antenna gain is a key parameter in the performance of wireless systems. In addition, the cost of producing antennas is also an important factor to take into account. The present invention has been devised with the foregoing in mind.